Chiral resolution of racemic amines is a very important process for the pharmaceutical industry, as these amines are useful intermediates for the production of various antibiotics or as inhibitory transmitters to control some neurological disorders. The biological activities are strongly dependent on their absolute configuration and both S and R isomers have potential therapeutic uses. Traditionally, chemical chiral resolution is achieved by utilizing a chiral compound such as an acid to stereo-selectively react with one of the isomers, and thereby facilitating the separation of the enantiomers.
3-Aminopentanenitrile (APN) is a commercially available compound, which may exist in two enantiomeric forms, R-APN and S-APN. Typically, chiral resolution of R-APN is achieved by reacting a racemic mixture of APN with dibenzoyl-L-tartaric acid, which preferentially binds to R-APN. The resulting R-APN-dibenzoyl-L-tartrate salt may be isolated and subsequently reacted with methanesulfonic acid to produce R-APN-methanesulfonate salt.
Efficient, economic and convenient alternative methods for the chiral resolution of aminopentanenitriles are needed. Biocatalytic processes can furnish the requisites, as enzymes often exhibit excellent enantioselectivities. Further, enzyme reactions are well characterized for their specificities and mild reaction conditions. The application of enzymes for the chiral resolution of APN has not been disclosed.